Stapling machine



0c; 31, 1939. L. BRbWNSTEIN 2.118354 STAPLING MACHINE Filed Feb. 17,1936 3Shee'ts-Sheet 1 81 v INVENTOR Louis Browmslz'n BY ATTORNEY Oct.31, 1939. BROWNSTEl N STAPLING MACHINE Filed Feb. 17, 1936 3Sheets-Sheet 3 INVENTOR Louis Brow/7.51am

WC ATTORNEY Patented Oct. 31, 1939 UNITED STATES PATENT OFFICE STAPLINGMACHINE Application February 17, 1936, Serial No. 64,307

24 Claims.

This invention relates to stapling .machines for the sealing ofcontainers made of corrugated board or other materials, and is intendedprimarily to constitute a further development of the invention ofEmanuel R. Posnack described and disclosed in Letters Patent No.1,945,377 issued January 30, 1934, whereby adjacent flaps of a cartonare secured together by a drive effected from one side of the materialwithout the use of any underlying blade or anvil, my invention beingparticularly, though not exclusively, adapted to employ the staplesdisclosed and claimed in Letters Patent No. 2,008,086 granted on July16, 1935, upon the application of Wendell L. Sorenson.

In the said Posnack invention, the driving plunger is actuated by aspring-release or trip mechanism for severing and driving a staplefrom astrip of staples fed into the machine through the rear portion thereof.It is within the contemplation of my invention to improve upon thisconstruction by simplifying the driving mechanism to effect a plungerstroke by direct manual or mechanical pressure, and also to provide amethod of feeding staples into the machine through the front portionthereof. And it is also -within the contemplation of this invention toenable the front feeding operation to be effectuated in a quick and easymanner, whereby the strip of staples will be retained within the machineand held against being projected forwardly until the machine is placedinto condition for use.

It is still another object of my invention to enable a machine of thischaracter to operatively receive therein a variety of sizes of stapleseither without any adjustments whatsoever, or with only a relativelysimple adjustment if at all necessary.

It is also within the contemplation of this invention to improve uponthe anvil mechanism in the said Posnack invention by eliminating therotary anvil actuator and substituting therefor a simpler device readilyadjustable for the timing of the anvil retraction.

Another object of my invention is to enable a machine of this class tobe constructed at a low cost by providing not only inexpensive andreadily fabricated elements, but also a special arrangement of parts forenabling certain combinative elements to be independently assembledoutside of the frame of the machine, to be thereafter convenientlyinserted to produce a completely assembled unit.

And another object is to produce a more convenient and effective stitchby causing the driven staple head to be imbedded and virtuallycountersunk into the material being stapled.

Still another object of this invention is to enable certain elementsthereof, such as the feeding and driving mechanisms, to be operativelyandefficiently employed" in various kinds of stapling machines includingthose which employ an anvil underlying the material being stapled asdistinguished from those having anvils overlying the material, asexemplified by the aforesaid Posnack invention.

Other objects, features and advantages will appear from the drawings andthe description hereinafter given.

Referring to the drawings:

Figure 1 is a vertical cross section of the machine showing the parts intheir normal inoperative position.

Figure 2 is a sectional plan of Figure 1 taken along line 22.

Figure 3 is a fragmentary vertical cross section of the machine showingthe position of the parts upon the completion of the down stroke of theplunger.

Figure 4 is a vertical transverse section of Figure 3 taken along line4-4, a portion of the plunger being broken away to show the partstherebehind.

Figure 5 is a fragmentary vertical cross section of Figure 4 taken alongline 55, showing the staple-retaining pawl in its non-engaging position.

Figure 6 is a view similar to Figure 5 showing the staple-retaining pawlin its engaging or operative position, with the front plate of themachine raised.

Figure 7 is a vertical section of Figure 4 taken along line 'l-l,showing the anvil and anvil actuator in their inoperative positions.

Figure 8 is a view similar to Figure 7 showing the anvil and anvilactuator in their retracted positions.

Figures 9, 10, 11 and 12 are semi-diagrammatic fragmentary front viewsof a form of my invention illustrating the relative positions ofplunger, staple, anvil and material being stapled during a completestroke or clenching cycle.

Figure 13 shows the final position and shape of the fully clenchedstaple after completion of the stroke illustrated in Figures 9 to 12inclusive.

Figure 14 is a fragmentary vertical section of Figure 4 taken along line5-5 showing the position of the parts preparatory to the loading of thedevice with a strip of staples, and

Figure 15 is a view similar to Figure 14 showing the strip of staplespartially inserted during a loading operation.

In the drawings the frame to contains at the forward part thereof theshaft II upon which is pivotally mounted the forward extremity of thedriving lever l2, the underside of which contains a slotted portion l3the lateral walls of which support the pin l4 extending transverselyacross the slot. Pivotally mounted upon pin I4 is the driving arm I5,preferably though not necessarily of channel-like structure, the forwardend of said arm being rotatably mounted upon the pin l6 which issuitably secured to the ears or walls l1 and it (see Figure 4)associated with the driving plunger [19. The preferred construction isto have the said ears l1 and I8 integral with the plunger and bent backat right angles thereto. .Extending transversely across the forward partof the driving arm i5 and suitably supported by the channel wallsthereof is the pin 2| to which is anchored the lower portion of spring22, which extends upwardly through the aperture 23 in the lever, theupper portion of the spring being suitably anchored to the pin 24extending transversely across said aperture and suitably secured to theforward portion of the lever l2.

The plunger l9 (see Figure 4) in the preferred form thereof, containsthe reduced driving portion 25, the full width portions 26 and 21, andthe upwardly extending portions 28 and 29, the lateral edges of certainof said portions being in slidable engagement with suitable slots in theframe of the machine. It should be noted that the said portions 28 and29 are each of relatively narrow width so as to form a spacetherebetween to reduce the weight and stock of the plunger and provideroom for any parts that may be required to protrude therethrough due todimensional design. The front plate 30 is positioned within the frontslotted portions of the frame and is adapted for vertical slidablemovement therein to either cover or expose the plunger and associatedparts. The said plate contains a protruding element 3| adapted formanual manipulation to enable the plate to be raised or lowered; and theupper portion of the plate is preferably bent over at right angles torest upon the depressed portion of the knob or top portion 32 of themachine which is suitably attached to the framework thereof.

The strip of staples 33 is carried by the staple rail 34 which issubstantially U-shaped in crosssection and having the upper lateralwalls thereof preferably flared outwardly for supporting the uppermostportions of the staples. Said staple rail extends longitudinally withinthe machine, the base 35 of the rail being suitably aflixed to the baseplate 36 by means of the screws 31 and 38. The said base 35 contains anupwardly and rearwardly extending portion or tongue 39, preferablyformed integral therefrom, to which the spring 40 is anchored, saidspring extending forwardly therefrom, around the roller 4| mounted fromthe front lateral walls of the rail, and back again longitudinallythrough the push member 42 to be anchored to the downwardly extendingwall 43 thereof, said push member being slidably mounted over the rail34 and adapted for yieldable engagement against the rear portion of thestaple strip 33 under the influence of said spring 40.

The machine is provided with a hold-down plate 44 which extendssubstantially along the entire length of the machine within the housing45, the rear portion thereof being preferably bent downwardly and thenforwardly to form a U- shaped extremity the vertical wall 46 thereofbeing in constant engagement with the spring 41 interposed between saidwall and the rear wall 48 of the housing, the lower forwardly bent wall49 being suitably attached preferably by the screw 50 to the base plate36 of the machine. The action of the spring 41 is to normally urge theholddown plate 44, base plate 36, staple carrier 34, and attached partsin a forwardly direction.

The forward part of said hold-down plate contains the two upwardlydisposed extensions or ears El and 52 which support the transverse shaft53 to which are afiixed the pawl 54 and the -wardly extending arm 55,the said shaft having suitably associated therewith or preferablymounted thereover and anchored to the holddown plate the spring 56rotatably actuating the said shaft 53 to normally urge the arm 55 161'-wardly and the lower terminal edge of the pawl 54 downwardly foroperative engagement with the staple strip, as will be more specificallyhereinafter described. It will be noted that the holddown plate 44contains the aperture 51 therein to permit the entrance therethrough ofthe operating terminal of said pawl,

A hold-down screw 58, preferably in threaded engagement with a lug 59forming an integral part of the frame, extends downwardly within themachine, the terminal portion 66 extending through the aperture 6| ofthe hold-down plate 44, the shoulder 62 of the screw being in engagementwith the upper surface of said hold-down plate. The upper portion of thesaid screw is. in threaded engagement with the lock nut 63.

The aforesaid base plate 36 is slidably movable within the slottedportion 64 at the bottom of the housing 45, said plate containing arecess 65 there;- in (see Figure 2) into which extends the terminalportion of the shank of screw 66 in threaded engagement with the boss 61forming an integral part of the base of the housing. The front part ofsaid base plate 36 contains a depressed portion 66 extending forwardlyand constituting the body of the retractable anvil of the machine, theextreme forward portion containing the anvil lip 69 (see Figures 4 and7) adapted in its forward position to underlie the reduced portion 25 ofthe plunger I9. The said base plate contains an aperture 16 therein (seeFigures '7 and 8), preferably rearwardly of the anvil portion thereof,the anvil actuator 1|, preferably of channel-shaped structure, havingthe rear extremity 12 thereof extending into said aperture and inoperative engagement with the walls thereof. The front of said anvilactuator 1| contains the transversely disposed shaft 13 upon which ismounted the roller 14 the forward portion of which normally underliesthe shoulder 15 of the plunger I9, as shown in Figures 4 and 7.Extending vertically through and in threaded engagement with the base ofthe anvil actuator is the adjusting screw 11, the lower extremity 18thereof being in abutment with the base of the machine. Extendingupwardly through the base plate 36 is another screw 19 also in threadedengagement with the anvil actuator 1|, the head portion of the screwbeing exposed to view and preferably readily accessible.

In the operation of this device, a downward movement of the lever |2will cause the applied pressure to be transmitted through the drivingarm |5 to the plunger l9 to cause a driving stroke thereof during whichthe lowermost edge of the plunger will disengage the foremost staple onthe staple strip 33 and drive it downwardly towards the material beingstapled. During the course of the operative stroke, the lowermostportion of the V-shaped indenture 16 (see Figures 4 and 9) of the staplewill come into engagement with the lip 69 of the anvil (see Figure 10)and at a predetermined point the shoulder 15 will engage the roller 14(see Figures 8 and 12) to force the anvil actuator 1| rearwardly,resulting in a corresponding rearward movement or retraction of theentire base plate and anvil against the action of spring 41, therebypermitting the continued movement of the plunger to complete the drivingoperation by forcing the top of the staple flush against the material(see Figure 12). It should be noted that inasmuch as the V-shapedindenture contacts with the non-yieldable lip 89, the upper portion ofthe staple becomes flattened against the material (see Figure 11) tocause a clenching of the prongs thereof within the work, substantiallyin accordance with the description and drawings in the aforementionedpatents of Posnack and Sorenson. Upon a release of the lever l2 aftercompletion of the driving operation, the spring 22 will cause a returnof said lever to its normal inoperative position, and the base plate 36with anvil 68 will be projected forwardly under the influence of spring48 to its initial position at the beginning of the cycle.

The retraction of the anvil and base by the action of the anvil actuatorcauses a corresponding retraction of the attached rail 34 and thehold-down plate 44, thereby removing any possible obstruction to theeasy downward movement of the plunger, the apertures 51 and BI in thehold-down plate permitting such movement without interference with thescrew 58 or pawl 54. The entire base plate 36 is limited in its forwardmovement by the engagement of the shank of screw 65 with the rear wallof the slot 65.

In feeding the staples into the machine, the front plate is raised andthe staple strip inserted upon the staple rail 34, the rearmost staplebeing brought into engagement with the foremost portion of the pushmember 42 which is positioned at the front of the machine due to thepull of the sprin 40 (see Figure 14). By pushing the entire striprearwardly against the action of said spring 40, the terminal portion ofthe pawl 54 will slidably engage the staples during the aforesaidoperation of inserting the strip, due to the action of spring (seeFigure 15). Upon a release of the manually applied pushing pressure, theoperating edge of the pawl 54 will enter the nearest adjacent spacebetween the tops of two contiguous staples, and will hold the stripagainst forward movement, thereby yieldably retaining it in place (seeFigure 6). During this entire operation, while the front plate 30 is inits raised position, the arm 55 will be protruding through the front ofthe machine as shown in Figure 6. As soon, however, as the front plate30 is lowered, the arm 55 will be pushed back rearwardly thereby torotate the shaft 53 in a counterclockwise direction, thereby raising thepawl 54 out of engagement with the staple strip (see Figure 5). In thismanner the push member 42 is left free to urge the staple stripforwardly for operative coaction with the plunger.

This machine constituting my invention is adapted, in accordance withone of the objects thereof, to operatively employ a number of differentsizes of staples, the only requirement being that the distance acrossthe indenture of the various sizes be substantially the same. In otherwords, when this requirement is met staples of different lengths oflegs, different angles of the indenture and different cross-sections canbe employed. It is desirable, however, that proper provision be made foradjusting the machine for staples of different cross-sections. If, forexample, the hold-down plate 44 is placed at too great a distance abovethe staple strip, the most forwardly positioned staples may have atendency to tilt over forwardly at an angle, especially while the firststaple is being severed. It is for this reason that it is advisable thatthe hold-down plate 44 be positioned at such a distance above the sta- Ojdl bl! ple strip as to provide sufficient clearance for movement andyet close enough to the staple strip to hold the forward portionsthereof in their vertical positions. The adjusting screw 58 is thereforemanipulated to either slightly lower said hold-down plate in accordancewith requirements, or to permit it to raise itself to a higher level inaccordance with its normal tendency due to its resiliency. In thisconnection it should be noted that the hold-down plate is mounted nearlyat the rear of the housing, and hence the entire upper portion of theplate can be moved 'up or down slightly due to the resiliency of thematerial out of which it is made. In this mannner, staples of variouscross-sections can be accommodated for eflicient operative use withinthe machine without any other adjustment except that of a simple turn ofa screw, if such an adjustment should at all be necessary.

Should it be necessary to vary the timing of the anvil, that is the timeof retraction thereof with respect to the movement of the plunger, thescrews 11 and 19 are manipulated to raise or lower the position of theroller, in obvious manner,

thereby enabling the plunger to actuate the member H at predeterminedpoints during its operative stroke. Such adjustment need normally bemade during the original assembly of the machine.

The forward part of the base of the machine (see Figure 4) contains twoupwardly curved flanges 80 and 8| flanking the anvil portion 58. Whenpressure is applied to the knob 32 simultaneously with the operation ofthe lever, the said anvil portion will compress the underlying materialand slightly impress itself therein (see Figures 9 and 12), so that whena staple is operativcly forced into the material, the top thereof willbecome imbedded therein to form a countersunk stitch such as is shown inFigure 13, producing a firm seal and presenting a smooth upper surface.

It should be observed that although the front feed hereinbeforedescribed has been employed, in accordance with the drawings formingpart of this specification, in conjunction with a particu lar type ofmachine having an anvil adapted to overlie the material, it is of courseunderstood that the same feeding means can be employed in other staplingdevices employing the conventional structure containing an anvilunderlying the material.

It will also be observed that the design hereinabove described is verycompact and economical of space. The feed spring 40 and the mountingstherefor are contained within the lateral walls of the rail 34 (seeFigures 2 and 4); the anvil actuator H is contained at one side of thestaple rail (see Figure 2), and the staple-strip retaining means 54 ispositioned on the other side, all of which combines to produce a verycompact structure. The construction of the plunger should beparticularly noted, in that it contains certain elements which serve anumber of functions as hereinbefore explained, the entire plunger beingadapted for fabrication from a stamping die.

The cost of manufacture of this device can be rendered relatively low inView of the feasibility of assembling certain parts in combinative unitsoutside of the frame. The plunger l9, the lever l2, the driving arm l5and the spring 22 can be assembled in one unit; and the base plate 36,the staple rail 34, the hold-down plate 44, the anvil actuatingmechanism and the aforesaid pawl retaining means can similarly beindependently assembled. Thereafter both combinative units can beinserted into the machine to complate the assembling job.

Although the above-described machine is of the manually operated type,it is of course apparent that the mechanical features thereof can beemployed as well in an electrically or foot operated unit; and it isfurther understood that the various embodiments above described andshown in the drawings are illustrative of my invention and not employedby way of limitation, inasmuch as numerous changes and modifications maybe made within the scope of the appended claims without departing fromthe spirit of this invention.

What I claim is:

1. In a stapling machine, a plunger, a pivotally mounted lever, adriving arm pivotally connected to said plunger and lever forreciprocatingly actuating the plunger, a spring anchored to said leverand attached to said arm for yieldably resisting the driving movement ofthe latter, a retractable anvil adapted to overlie the material beingstapled and in its normal position underlying the plunger, and meanscoacting with said plunger and anvil for retracting the latter from saidnormal position at a predetermined point during the stroke of theplunger.

2. In a stapling machine, a reciprocating plunger, a driving lever theforward extremity of which is pivotally mounted at the front of theframe of the machine, said lever containing a hole extending through thefront portion thereof and a slot at the bottom thereof, a pin extendingtransversely across said slot and suitably supported by the lateralwalls thereof, a driving arm one end of which extends into said slot andis pivotally mounted on said pin, the other end of the arm beingpivotally mounted on the plunger for operatively actuating it, a secondpin attached to the lever and extending transversely across said holetherein, a spring attached to said driving arm and extending upwardlythrough said hole and anchored to said latter pin, a retractible anviladapted to overlie the material being stapled and in its normal positionunderlying the plunger, and means coacting with said plunger and anvilfor retracting the latter from said normal position at a predeterminedpoint during the stroke of the plunger.

3. In a stapling machine, a reciprocating plunger containing a bottomdriving portion of reduced width flanked by two outwardly extendingshoulders thereabove and having an intermediate portion the sidesthereof being bent back and perforated with two axially aligned holes, apin extending through said holes and suitably supported by the sides ofthe plunger, a driving arm pivotally mounted on said pin, a drivinglever pivotally mounted on the frame of the machine and having pivotallysecured thereto said arm for operatively actuating the plunger, aretractible anvil adapted to overlie the material being stapled and inits normal position underlying the plunger, and means operativelyconnected with said anvil and engageable by one of said shoulders of theplunger for retracting the anvil from said normal position at apredetermined point during the stroke of the plunger.

4. In a stapling machine, a plunger, means to reciprocally actuate theplunger, a retractible anvil adapted to overlie the material beingstapled and in its normal position underlying the plunger, and an anvilactuator movable longitudinally within the machine and coactivelyconnected to said anvil, the forward portion of said actuator beingnormally in the line of travel of the plung-- er and engageable therebyduring its downward stroke to cause a rearward movement thereof and aconsequent retraction of the anvil from its said normal position.

5. In a stapling machine, a plunger, means to reciprocally actuate theplunger, a retractible anvil adapted to overlie the material beingstapled and in its normal position underlying the plunger, and an anvilactuator movable longitudinally within the machine and coactivelyconnected to said anvil, the forward portion of said actuator havingrotatably mounted thereon a roller normally in the path of the plungerand operatively engageable thereby during its downward stroke to cause arearward movement of the actuator and a consequent retraction of theanvil from its said normal position.

6. In astapling machine, a reciprocating plunger containing a bottomdriving portion of reduced width flanked by two outwardly extendingshoulders thereabove, means to reciprocally actuate the plunger, aretractible anvil adapted to overlie the material being stapled and inits normal position underlying the plunger, and an anvil actuatormovable longitudinally within the machine and coactively connected tosaid anvil, the forward portion of said actuator being normally in theline of travel of the plunger and operatively engageable by one of saidshoulders of the plunger during its downward stroke to cause a rearwardmovement of the actuator and a consequent retraction of the anvil fromits said normal position.

7. In a stapling machine, a reciprocating plunger containing a bottomdriving portion of reduced width flanked by two outwardly extendingshoulders thereabove, means to reciprocally actuate the plunger, aretractible anvil adapted to overlie the material being stapled and inits normal position underlying the plunger, and an anvil actuatormovable longitudinally within the machine and coactively connected tosaid anvil, the forward portion of said actuator having rotatablymounted thereon a roller normally in the path of the plunger andoperatively engageable by one of said shoulders of the plunger duringits downward stroke to cause a rearward movement .of the actuator and aconsequent retraction of the anvil from its said normal position.

8. In a stapling machine, a plunger, means to reciprocally actuate theplunger, a retractible anvil adapted. to overlie the material beingstapled and in its normal position underlying the plunger, an anvilactuator movable longitudinally within the machine and coactivelyconnected to said anvil, the forward portion of said actuator beingnormally in the line of travelof the plunger and engageable therebyduring its downward stroke to cause a rearward movement thereof and aconsequent retraction of the anvil from its said normal position, andmeans coactively engageable with said actuator to adjustably raise orlower the said forward portion thereof to vary the timing of theoperative engagement of the plunger and the anvil actuator. V

9. In a stapling machine, a plunger, means to reciprocally actuate theplunger, a retractible anvil adapted to overlie the material beingstapled and in its normal position underlying the plunger, an anvilactuator comprising a longitudinally disposed member movable lengthwisewithin the machine the rear end of said member being coactivelyassociated with said anvil, the forward portion of said actuator beingnormally in the line of travel of the plunger and engageable therebyduring its downward stroke to cause a rearward movement thereof and aconsequent retraction of the anvil from its said normal position, andscrew means extending substantially vertically through said member andin threaded engagement therewith for adjustably raising and lowering thesaid forward portion of the actuator to vary the timing of the operativeengagement of the plunger and the anvil actuator.

10. In a stapling machine, a plunger, means to reciprocally actuate theplunger, a base plate slidably movable lengthwise along the lowerportion of the machine and extending substantially along the entirelength thereof and forming a bottom closure therefor, an anvil at theforward part of said base plate and having the front portionthereofnormally underlying the plunger, and means coacting with said plungerfor moving the base plate and anvil rearwardly to retract the said frontportion of the anvil from its normal position.

11. In a stapling machine, a plunger, means to reciprocally actuate theplunger, a base plate slidably movable lengthwise along the lowerportion of the machine and extending substantially along the entirelength thereof and forming a bottom closure therefor, an anvil at theforward part of the base plate and integral therewith, said anvilextending downwardly below the level of said plate nd containing aforwardly protruding lip normally underlying the plunger, and meanscoacting with said plunger for moving the base plate and anvilrearwardly to retract the said lip from its normal position.

12. In a stapling machine, a plunger, means to reciprocally actuate theplunger, a base plate slidably movable lengthwise within the lowerportion of the machine, an anvil at the forward part of said base plateand having the front portion thereof normally underlying the plunger,and an anvil actuator comprising a longitudinally disposed membermovable lengthwise within the machine; the said base plate containing anaperture therein rearwardly of said anvil, the rear end of said memberbeing operatively engageable with a wall of said aperture, the forwardportion of said actuator being normally in the path of the plunger andoperatively engageable thereby during its downward stroke to cause arearward movement of the actuator and engagementof the latter with thewall of the aperture and a consequent retraction of the base plate andanvil from said normal position.

13. In a stapling machine, a plunger, means to reciprocally actuate theplunger, a base plate slidably movable lengthwise within the lowerportion of the machine, an anvil at the forward part of said base plateand having the front portion thereof normally underlying the plunger,and means coacting with said plunger for moving the base plate and anvilrearwardly to retract the said front portion of the anvil from itsnormal position; said base plate containing along a lateral edge thereofa notched portion, and an element attached to the frame of the machineand engageable with said notched portion to limit the longitudinalmovement of the base plate and associated parts.

14. In a stapling machine, a reciprocating plunger, a retractible staplerail substantially U- shaped in cross-section and normally extendinglongitudinally within the machine to the Plane of the plunger, meansassociated with the plunguoal on HUGH er engageable with the rail forretracting it from its said normal position, a spring mountingpositioned at the front of the rail and between the lateral wallsthereof, a push member slidably mounted over said rail, and a springextending lengthwise between the lateral walls of said rail, said springhaving the lower rearmost end thereof suitably attached to the base ofthe rail and extending forwardly and around said mounting and thenrearwardly, the upper rearmost portion of the spring being suitablyattached to said push member to constantly urge it forwardly.

15. In a staplingmachine,areciprocatingplung er, a retractible staplerail substantially U- shaped in cross-section and normally extendinglongitudinally within the machine to the plane of the plunger, meansassociated with the plunger and engageable with the rail for retractingit from its said normal position, the upper portions of the lateralwalls of the rail being flared outwardly and adapted to support stapleshaving angulated legs and V-shaped tops, a roller positioned at thefront of the rail and rotatably mounted between the lateral wallsthereof, a push member slidably mounted over said rail and containing atthe rear thereof a depending wall, the base of the rail containing anupwardly extending element, and a spring extending lengthwise betweenthe lateral walls of said rail, the spring having the lower rearmost endthereof anchored to said element and extending forwardly around saidroller and then rearwardly, the upper rearmost portion of the springbeing attached to said depending wall to constantly urge the push memberforwardly.

16. In a stapling machine, a plunger, means to reciprocally actuate theplunger, a base plate slidably movable lengthwise within the lowerportion of the machine, a staple rail substantially U-shaped incross-section and extending longitudinally within the machine, the baseof the rail being suitably attached to said base plate, a springmounting positioned at the front of the rail and between the lateralwalls thereof, a push member slidably mounted over said rail, and aspring extending lengthwise between the lateral walls of said rail, saidspring having the lower rearmost end thereof suitably attached to thebase of the rail and extending forwardly and around said mounting andthen rearwardly, the upper rearmost portion of the spring being suitablyattached to said push member to constantly urge it forwardly; an anvilat the forward part of said base plate and having the front portionthereof normally underlying the plunger, and means coacting with saidplunger for moving the base plate, rail and anvil rearwardly to retractthe said front portion of the anvil from its normal position.

17. In a stapling machine, a plunger, means to reciprocally actuate theplunger, a base plate slidably movable lengthwise within the lowerportion of the machine, a staple rail extending longitudinally withinthe machine and suitably attached to said base plate, a hold-down plateextending to the extreme forward part of the rail and positioned apredetermined distance thereabove, an anvil at the forward part of saidbase plate and having the front portion thereof normally underlying theplunger, and means coacting with said plunger for moving the base platerearwardly to effect an operative retraction of the anvil.

18. In a stapling machine, a plunger, means to reciprocally actuate theplunger, a base plate slidably movable lengthwise within the lowerportion of the machine, a staple rail substantially U-shaped incross-section and extending longitudinally within the machine, ahold-down plate extending longitudinally of the machine, the forwardpart thereof being positioned a predetermined distance above the rail,the rail and holddown plate being suitably attached to said base plate,an anvil at the forward part of said base plate and having the frontportion thereof normally underlying the plunger, and means coacting withsaid plunger for moving the base plate with its said attached partsrearwardly to effect an operative retraction of the anvil.

19. In a stapling machine, a plunger, means to reciprocally actuate theplunger, a base plate slidably movable lengthwise within the lowerportion of the machine, a staple rail extending longitudinally withinthe machine and suitably attached to said base plate, a hold-down plateextending to the extreme forward part of the rail, adjusting means inoperative engagement with the forward part of said hold-down plate forvarying the distance thereof above the rail, an anvil at the forwardpart of said base plate and having the front portion thereof normallyunderlying the plunger, and means coacting with said plunger for movingthe base plate rearwardly to effect an operative retraction of theanvil.

20. In a stapling machine, a plunger, means to reciprocally actuate theplunger, a base plate slidably movable lengthwise within the lowerportion of the machine, a staple rail extending longitudinally withinthe machine and suitably attached to said base plate, a hold-down plateextending to the extreme forward part of the rail, a lug in the forwardpart of the frame of the machine, a screw in threaded engagement withsaid lug and in operative engagement with the forward part of saidhold-down plate whereby upon a manipulation of the screw the latterplate will be raised or lowered a predetermined distance above the rail,an anvil at the forward part of said base plate and having the frontportion thereof normally underlying the plunger, and means coacting withsaid plunger for moving the base plate rearwardly to effect an operativeretraction of the anvil.

21. In a stapling machine, a plunger, means to reciprocally actuate theplunger, a base plate slidably movable lengthwise within the lowerportion of the machine, a staple rail substantially U-shaped incross-section and extending longitudinally within the machine, ahold-down plate extending longitudinally of the machine and containing avertical portion at the rear thereof, the forward part of the platebeing positioned a predetermined distance above the rail, the rail andhold-down plate being suitably attached to said base plate, an anvil atthe forward part of said base plate and having the front portion thereofnormally underlying the plunger, means coacting with said plunger formoving the base plate with its said attached parts rearwardly to effectan operative retraction of the anvil, and spring means in engagementwith said vertical portion of the hold-down plate yieldably holding saidlatter plate, said base plate and attached parts in their normal,unretracted positions.

22. In a stapling machine, a plunger, means to reciprocally actuate theplunger, a base plate suitably movable lengthwise within the lowerportion of the machine, a staple rail substantially U-shaped incross-section and extending longitudinally within the machine, ahold-down plate extending longitudinally of the machine, the forwardpart being adjustably positioned over the rail, the rear portion of saidhold-down plate extending down vertically and then forwardly, theforwardly extending portion being attached to the said base plate, ananvil at the forward part of. said base plate and having the frontportion thereof normally underlying the plunger, and means coacting withsaid plunger for moving the base plate and attached parts rearwardly toeffect an operative retraction of the anvil, and a spring anchored tothe rear of the machine frame and in constant engagement with the rearvertical wall of said hold-down plate yieldably holding said latterplate, said base plate and attached parts in their normal, unretractedpositions.

23. In a stapling machine containing a front opening therein, a staplerail for slidably accommodating a strip of staples, staple pushing meansengageable with the said strip for constantly urging it forward, ahold-down plate extending to the extreme forward part of the rail andadjustably positioned a predetermined distance thereabove, the forwardpart of said plate containing two spaced upwardly disposed extensions, atransverse shaft rotatably supported by said extensions, a pawl aflixedto said shaft, the edge of the pawl being adapted in its operativeposition to engage said staple pushing means and said strip when theyare operatively positioned below the pawl, a forwardly extending armaffixed to said shaft and adapted to project through the front openingof the machine, spring means urging said pawl into its said operativeposition and said arm into its said projected position, a front plateslidably movable within the frame of the machine and positionedforwardly of said rail, said plate being adapted upon a movement thereoftowards the base of the machine to engage said protruding arm andactuate it rearwardly and cause a consequent retraction of the pawl fromits said operative position against the action of said spring means.

24. In a stapling machine containing a front opening therein, a staplerail for slidably accommodating a strip of staples, staple pushing meansengageable with said strip for constantly urging it forwardly, apivotally mounted pawl engageable with said staple pushing means whenthe latter is positioned below the pawl, said pawl when in its operativeposition being engageable with said strip when it is positioned belowthe edge of the pawl to hold the strip against forward movement, anindependent rotatably mounted arm operative associated with the pawl andin fixed relation thereto, said arm extending forwardly and beingadapted to project through.

the said front opening of the machine, spring means urging said pawlinto its said operative position and said arm into its said projectedposition, a front plate slidably movable within the frame of the machineand positioned forwardly of said rail, said plate being adapted upon amovement thereof towards the bottom of the machine to engage saidprotruding arm and actuate it rearwardly and cause a consequentretraction of the pawl from its said operative position against theaction of said spring means.

LOUIS BROWNS'I'EIN.

